Electrical Lighting

Electrical lighting 

Electrical lighting has following advantages, 

1. Cleanliness

2. Easy to control

3. Economical

4. Easy to handle

5. Steady output

6. Better reliability

7. Suitable for almost all purposes etc.

1 Introduction

Introduction 

As we know that almost all human activities

depends on light. Sun is a prime natural source

of light but artificial lighting plays almost main

role in our daily life. These artificial lights are

produced by mechanical lamps and electrical

lamps.

But due to poor performance the mechanical light

are totally replaced by electrical lights. The

electrical lighting are mainly used for

decorative purpose, advertising, traffic control ,

medical field and street lighting etc.

ILLUMINATION BASIC SCHEME

TOPICS

1 Introduction 

2 Nature of light

3 Terms used in illumination 

4 Law of illumination 

5 Electrical method of producing light

6 Source of light

7 Arc lamp

8 Filament lamp 

9 Gaseous discharge lamps

10 Sodium vapour lamp

11 Mercury Vapour lamp

12 Fluorescent tube

13 Neon lamp

14 Halogen lamp

15 Compact fluorescent lamp 

16 Candle Power and its measurement 

17 Lighting scheme

18 Street light

19 Flood lighting 

Conductor Size Calculations

1 Current carrying capabilty 

2 Voltage Drop 

3 Distance between the service pole to energy meter 

1 Current carrying capacity 

2 Voltage Drop

For single Phase Supply permissible voltage drop is equal to 

2% of Voltage + 1 Volt

For example: If a house is energized with single phase 230 volts supply then permissible voltage drop is equal to : 2% X 230 + 1 v

= 5.6 volts

For three Phase Supply permissible voltage drop is equal to 

5% of Voltage applied

For example: If a house is energized with three phase 430 volts supply then permissible voltage drop is equal to : 5% X 430 

= 21.5 volts

3 Relation between voltage drop of wire and permissible voltage drop

Voltage drop Should be less than Permissible voltage drop

Voltage drop     <        Permissible Voltage drop

Friends this topic is based all numarical so see this carefully and step by step 

Numaricals:

Problem 1 

A residential building is energized with single phase 230 volts 50 hz supply. The total current requirement by load is 13 amps. The distance between the service main to energy meter is 10 meters. Find out the size of aluminum wire lying between service mains to energy meter.

Ans

Supply voltage = 230 volts

Frequency = 50 hz

I = 13 Amps

Length = 20 meters ( both phase and neutral)

Permissible voltage drop = 2 X 230/100.     + 1 volt

          =    5.6 volts

For 2.5 square mm wire voltage drop @ 15 A    =   20/2.5

              @  1 A.    =   20/(2.5 X 15)

              @ 13 A.   =    (20 X 13) / (2.5 X 15)

              =      6.9 volts

For 4 square mm wire voltage drop @ 20 A    =   20/2.9

              @  1 A.    =   20/(2.9 X 20)

              @ 13 A.   =    (20 X 13) / (2.9 X 20)

              =      4.48 volts      

Problem 2

A residential building is energized with single phase 230 volts 50 hz supply. The total current requirement by load is 5 amps. The distance between the service main to energy meter is 20 meters. Find out the size of aluminum wire lying between service mains to energy meter. 

Types of circuits

Circuits

1 Open 

2 Closed 

3 Series 

4 Parallel 

Why Do we need of Bus bar

Need of bus bar 

Busbar distribute electricity with greater ease and flexibility than some other more permanent forms of installation and distribution. Sometimes spelled bus bar or bussbar, they are often metallic strips of copper, brass, or aluminum that both ground and conduct electricity.

Application of Bus bar

Uses of bus bar 

In electric power distribution, a busbar (alsobusbar) is a metallic strip or bar
, typically housed inside switchgear, panel boards, and busway enclosures for local high current power distribution.